Active and passive smoking and blood lead levels in U.S. adults: data from the Third National Health and Nutrition Examination Survey.

Lead is a component of tobacco and tobacco smoke. We examined the relationship between current, former, and passive smoking and blood lead levels in a nationally representative sample of 16,458 U.S. adults, aged 17 years or older, who participated in the Third National Health and Nutrition Examination Survey (1988-1994). We used linear and logistic regression modeling, adjusting for known covariates, to determine the relationship between smoking and blood lead levels. Geometric mean blood lead levels were 1.8 microg/dl, 2.1 microg/dl, and 2.3 microg/dl in never-smokers with no, low, and high cotinine levels, respectively. Levels were 2.9 microg/dl in former smokers and 3.5 microg/dl in current smokers. The adjusted linear regression model showed that geometric mean blood lead levels were 30% higher (95% CI = 24%-36%) in adults with high cotinine levels than they were in those with no detectable cotinine. Active and passive smoking is associated with increased blood lead levels in U.S. adults.